The field of this invention is a fluid introduction unit adapted for use in high pressure wells which require the introduction of highly corrosive fluids for well treatment purposes.
The use of various corrosive fluids, such as fluids containing sand, for fracturing, acidizing or other treatment of high pressure wells is part of the present well treatment technology. Generally, such corrosive fluids are introduced into a housing mounted in line with other production wellhead equipment having production tubing extending through a common central bore. In the past, the introduction of well treatment fluids through such housings has caused damage to the production tubing extending through the common bore, particularly due to the impingement of such corrosive fluids against the production tubing.
One way to avoid this problem has been to simply remove the production tubing prior to fracturing. This is an expensive operation requiring the well to be "killed." The killing of a well is accomplished by introducing extremely heavy fluids into the well, which fluids must be removed before production can resume. Removal of the heavy fluids is expensive, and, occasionally, problems are encountered in reviving such wells to production.